Study says NYC cheaper than London, but they're greener

The author of a new report says it's not a competition. But if it were, New York City would win for its affordability, and London for its programs to prevent climate change.

The study examines 14 factors. It finds, among other things, that Londoners are six times more likely to be robbed or assaulted than New Yorkers; and the London cost of living is nearly 40 percent higher.

But while the cities have similar populations, London has less than half the number of homeless.

The study was done by New York University's Schack Institute of Real Estate, the Urban Land Institute and London South Bank University.